Concentration of liquors in multiple effect and apparatus therefor



Aug. 27, 1935. A. R. JAHN CONCENTRATION OF LIQUORS IN MULTIPLE EFFECT AND APPARATUS THEREFOR Filed Jan. 18, 1934 5 Sheets-Sheet l HTTORNE Y Aug. 27, 1935. A. R. JAHN 2,012,668

CONCENTRATION OF LIQUORS IN MULTIPLE EFFECT AND APPARATUS THEREFOR Filed Jan. 18, 1934 3 Sheets-Sheet 2 Fig. 2.

Aug. 27, 1935. A. R. JAHN 2,012,668

CONCENTRATION OF LIQUORS IN MULTIPLE EFFECT AND APPARATUS THEREFOR Filed Jan. 18, 1934 5 Sheets-Sheet 5 Patented Aug. 27, 1935 CONCENTRATION OF LIQUORS IN MULTI- P1 13 EFFECT AND APPARATUS THEREFOR,

f Alfred Reinhold n, L n on, En and Application. January 18, 1934, Serial No. 707,227 111G113?! Brita Janua y l9,'193.3

5 Claims, (Cl. 159- 20) invention relates to an improved method {or the thickening or concentration of trade liquors, :and to the construction of plant in which this may be accomplished.

A principal object of the invention is to render a method more efficient and continuous, and

to make the construction of the plant less expensivte particularly by the saving of the wet air p mnwhichit has :been usualto employ in such 'a'plant and which is of considerable size, being DQi' h 051315 as regards instalment and maintenance, owing to the difiiculty of maintaining the said air pump efficient when dealing'with icondensate, including acid or other chemical contentswhichcause deterioration of the working Surfaces.

The principle used according to this method is that by passing the liquor. to be concentrated through a series of low temperature heating and separating units from which the final vapour is removed from a cooled condenser, a draught throughthe interconnecting series is obtained; :by means of an independent steam injector or :injectors, one of which in communication with :the condenser is applied to the last heater unit, the heat of the steam is moderated by the air and the non-condensable gasentrained from the cooled condenser,. and at the same time the gdraught through the system is maintained by the partial vacuum in the condenser assisted by the actionof the injected steam.

' The accompanying drawing, Fig. 1, illustrates a plant with twolarge heaters and two small heaters, the heaters being in series and each being provided with a circulatoror vapour separator. fi ureisto some extent diagrammatical in order to elucidate the' working of a complete plant Fig.' 2 showsin detail the connection between the condenser J ,andthe heater D and the air a ss ll-L I H fig. 3 is a detailview of the injector V3.

Fig isa sectional view of the connectionbetween the heater A and the heater B; and 1 Eig.,,5, shows ,a pair of heaters arranged in Para le a V 7 Described shortly, liquoris supplied from a vat to the-first heater A,;and passes through the tpbesthereot in theform ,ofsliquor andvapour, the apour onreaching .the first separator E beiflfi fiflfiifflfifiii irom hel quor which is. thus on .gst reted and theeon nt tedl quor d p sit d at the bottom of the separator, from which part peek throu hthe heater and a part passes nto the.pextliefiiterthrough the tubes of .which itrises, while the vapour and/or-air also contains ing moisture passes by a pipe 8 from the first separator to the space outside the tubes of the second heater, B. There being no specific heat supplied to this second :heater B which is at a reduced pressure, condensation of the vapour would take place .on .the outside of the tubes :25

so as'to heat the tubes to a lesserdegree than 1 those in vthevfirst heater, but suificient to again .causeevaporation of the liquor within the tubes, the condensate running down to the lower tube plate, and beingcarried away by a pipe 9 therefrom. Y

The same process is repeatedthroughthe rurther heaters, say a third and a fourtht from the final separator attached to the fourth heater, the concentrated liquor is drawn ofi-by apump and delivered toatank, While the hot vapour and air pass through the condenser on the lower tube plate of which the condensate, which'is .mostly waste water, collects, while the air and non-condensable vapour having now reached a cool temperature is delivered byentrainment with the steam; the air and non-.condensable'vapour undergoes a final. cooling in condenser J and is returned through the pipe l4 being entrained with the-steam through the' injector- V2' to the heating space ofthe last heater D. This deliv ery serves to create a suction through the whole plant including thecondenser at the same time that the heat and the steamoperating the in jector is moderated in --the heating of the last heater. A delivery pipe from-this last heater carries the air back to the steamstreain of an in"- jector supplying heat to the first heater, being again usefulin' moderating the heat supplied thereto. 7 f

Liquoris supplied-from a vatorother container I through a cock 111130 a pipe "Z leading'to the base 3 of the first tubularheaterA and rises'in tubes 4, where-it isheatedby steam irom'i ctors VI and VBsuppliedwith steam from a source, such as waste exhaust steam, forex ample {roman engine if available at 25 1bs. pressureper square :inch, or a higher pressure stamzfjlhe heated liquoris evaporated and the liquor'mixed I the .baseiof -the-second heater-B over-a pipe 1. The hot vapour and air separatedofi in thefirs't separator E flows through a pipe 8 to the tubes of the second heater B and by heat exchange the concentrated liquor in the tubes of the second heater B isevaporated at a lower temperature ually reduced temperature and pressure is ob-. tained by continuing the proce'ss'th'rough to the third heater C and separator G and finally to the fourth heater D and separator H, fromwhich the liquor in highly concentrated form is withdrawn through a pipe I by a pump P', driven by' an engine-driven pulley K, and is delivered over a-pipe. to atank [2;

' Heating of the last heaterD is effected primarily by a steam injector .VZsuppliedwith steamat a suitabletemperature and. pressure in accordance with the conditions toprevail in the last stage, this injector beingconnectedto an air-expansion vessel I 3 connected by apipe. M to the tubular condenser J. through. the tubes ofwhichflows coolingwater froma high levelsupply tank. l5. s; The vapour and .gases resulting fromthe separation in the fourth separator H are delivered over a pipe IE to the condenser J, wherein the condensatecollects on' the lower. tube plate, and the, air and ,non-Mcondensable: gases pass ..to the steam, stream from the injector V2. through the vessel l3,.,.and entrain with the steam into the heating; spaceof the last heater, D. 4 By this entrainment, suctionor vacuum is created and maintained in the condenser and through the whole, plant and at the same time the steam being delivered to, the last heaterD is tempered ormoderated to suit the low temperature conditionsof thelast stage., I;

The injector V3 of the first heater A isconnectedby a pipe I! to the fourthheater D, so that the air and othernon-conden'sable gases mainly originating from the condenser J are entrained with the steam stream passing from the injector V3 and thereby tempers and modifies this steam according tothe required condition in the first stage. Similarlytheinjector Vi is connected by a pipe l8 to -the,pipe:8 leading from the separator E to the heater B, so that the steam passing from, he injector Vi, entrains with it part of the vapour inthejpipfi 8 and; is also moderated. Thus a very effective control of the heatapplied to the heaterA is obtained, the condensate and air accumulating in theheater A being discl iarged to atmosphere through a steam trap l9 by means of the slight pressure resulting from the steam introduced into the heating space of the heater A by the injectors VI and' V3.v This pressure in the heaterA may be as low asl /z lbs. per square inch, the steam expanding down to thepressure which may be measured by the pressure gauge P. a

The condensate collecting on the loweritube plate4a. of theheating chambers of the;heaters B, C and Dis withdrawn by suction from the C011? denser J over the, pipes 9, passing through air vessels 20, 2|, which in regulating the flow of the condensate ensure eifectiVe,,.de-aeration of the intermediate and final heaters and providea mea s .0? 1 1F 48, the. heatpf th nd sat J hereinafter referred v The ejector V2 is connected to .:J through the expansion air vessel 3 in order to vapour surrounding the said tubes, suitable vacuum and temperature gauges PTG. being provided at the top of each separator.

Preferably the average temperature of the first separator A will be about 202 F. at a vacuum of about 5 and will gradually decrease from separator to-separator to 125 F. at a vacuum of about 26', or according to the liquor being treated. According to the invention-there is thus provided a process of thickening or concentrating liquors, which is continuous and is effectedat low temperatures, preferably below atmospheric boiling point and gradually reduced throughout the stages of the process; a point which is particularly advantageous H in preserving the quality and colour of liquors to be treated. .Moreover'by utilizing the steam both for heat- 7 ing and creating the suction throughout the plant gives. a considerable saving in expense; a four heater plant having a2400 square feet heating surface will give an evaporative output of about 800 gallons per hourand a steam consumption approximating 2000 lbs. per hour when concentrating acid bleached glue liquor from about 5% to 50% of glue in water; and the driving power savedwill approximate to 6 B. H.'P..

The apparatus and method according to the invention is applicable for concentrating trade liquors, such as milk, whey, gelatine, glue, lactic acid, tannic extract, apple, lemon; grape and tomato juices, vitamins, sugar, waste sulphite pulp cooking liquor, and liquors. of acolloidal nature including. slaughterhouse blood for conversion into, valuable adhesive. I

Fig. 5,shows an arrangement of heaters in parallel (i. e. with parallel temperatures). Referring tothe drawings the heater M corresponds to the heater A of Fig. 1' and is connected as 'regards its inter-tubular space with a steam trap 20a. by means of a, pipe I9, while the heater N corresponds to the heaterD of Fig. 1 and is connected in similar fashion .to the condenser J, except that the pipe 34 from the injector V2 is ,carried up through the base of the vapour separator H to near its outlet to-the'pipe l6.

The injector V3 is connected as before with the first heater M and the pipe 33 connects it as in the .largerplant with the outlet' of the intertubular space of the heater N. The pipes Hand.

28 apply steam as before and theli'quor is supplied by' the tank I introduced through the pipe lb...v I

pf In operation the heater M is used for pre heating the weak liquor, while the heater 'Nin con- -nection with the vapour separator H is used for liquor boiling and is connected as before with .the condenser J and it's evacuating accessories.

As shown in Fig. 5' the-moderated heating is done by the steam ejector V2 and the ejector VI is dispensed with in view of there being'only two heaters in the plant. 1 1

the'co'ndenser produce the vacuum suction through the plant, whilst the air exhaustion from the steam chamber N is operated by injector V3.

The relatively small amount of steam flowing through the latter injector condenses whilst performing the preheating in M, with the air along with the condensate water escaping through the pipe lSa to a steam trap 20a. Working in this way 28" of vacuum can easily be contained in the condenser J and at the liquor boiling point, whilst a vacuum of about 14" is maintained in the steam chamber of the heater M.

The other connections to the condenser are the same as in the plant shown in Fig. 1.

The relative size of the heaters described in these drawings is not material; although some are shown smaller than the others, they may be all of the same size.

I claim:

1. The combination in a liquor concentrating plant of a plurality of heaters, each having a tubular liquid compartment and a heating space surrounding same, an injector supplying steam to the heating space of the first heater, a vapour separator connected to the liquid compartment of the last heater, a cooling condenser, an injector supplying steam to the heating space of the last heater, an air expansion vessel in communication with the said injector and with the vapour space of the said condenser from which it collects the finally cooled air and non-condensable gases, a communication passage between the vapour separator and the vapour space of the condenser, pipe connections from the said air expansion vessel through the heater units for the removal from the latter of the condensate, a pipe connection from the last heater to the first heater including a supplementary steam injector, a steam trap, and a pipe connection from the first heater to the said steam trap.

2. A liquor concentrating plant having in combination a series of heaters, each having a tubular compartment and a heating space surrounding same, an injector supplying steam to the heating space of the last heater, a separator connected to the liquid compartment of each heater, a liquid conduit leading from the vapour space of each separator to the liquid space of the succeeding heater and a vapour conduit leading from the vapour space of each separator to the heating space of the succeeding heater, a cooling condenser, the vapour space of the latter communicating at one point with the vapour separator of the last heater of the series, and at another point with the said injector, means for conducting the air vapour contents of the last heater space to the first heater unit, a pump for the removal of the concentrated liquor from the final vapour separator and for pumping it to a receiving tank, and a second pump withdrawing the condensate from the condenser, whereby the process of concentration is rendered continuous.

3. In combination in a liquor concentrating plant a series of tubular heaters, a vapour separator connected by a collector with the tube space of each heater, a tubular passage leading from the top of each separator to the space surrounding the tubes of a succeeding heater, a tubular cooling condenser, a passage connecting its interspaces with the last vapour separator, a

water supply to the condenser tubes, an air expansion vessel in communication with the intertubular space of the condenser, a steam injector in a communicating passage between the said air expansion vessel and the inter-tubular space of the last heater, a pipe connecting the said spaces with the interspaces of the first tubular heater, passages connecting each vapour separator with a collecting space communicating with the tubular space of two adjoining heaters, means for removing the concentrated liquor from the final separator, and means for withdrawing the condensate from the condenser.

4. In combination in a liquor concentrating plant a series of tubular heaters, a vapour separator connected-by a collector with the tube space of each heater, a tubular passage leading from the top-of each separator to the space surrounding the tubes of a succeeding heater, a

tubular cooling condenser, a passage connecting its interspaces with the last vapour separator, a water supply to the condenser tubes, an air expansion vessel in communication with the intertubular space of the condenser, a steam injector in a communicating passage between the said air expansion vessel and the inter-tubular space of the last heater, a pipe connecting said spaces with the interspaces of the first tubular heater, a second steam injector included in the said pipe and communicating with the interspaces of the first heater unit, and a third injector connecting the said interspaces with the first vapour sepof the second heater for circulating flow, an air expansion vessel, a cooling condenser, the vapour space of the latter communicating at one point with the vapour separator of the second heater and at another point with the said air expansion vessel, a passage communicating between the air expansion vessel and the said injector, a passage communicating between the said injector and the vapour space of the vapour separator, a passage including a second steam injector connecting the inter-tubular space of the first heater with the inter-tubular space of the second heater, a liquor passage between the two heaters.- a connecting passage from the inter-tubular space of the condenser through the air vessel to the condensate collecting space of the second heater, a steam trap in communication with the inter-tubular space of the first heater, and means for removing the concentrated liquor from the said vapour separator and the condensate from the said condenser respectively. 7

ALFRED REINHOLD J AHN. 

